During World War II, copper metal was in short supply. In order to conserve the reserves of copper, the United States Government began to create pennies out of other materials. At first, they created pennies that were made of zinc plated steel. Due to the high reactivity of zinc, the pennies quickly corroded. These pennies were referred to as "white cents" or "steel cents". They were only produced for one year and copper was again used. As time went by, copper became too expensive to use and in the early 1980s, a new penny was developed. This penny used copper, but only on the outside. The more affordable metal zinc was used on the inside of the penny.
Often times the cost of a material greatly impacts it's use. Other things to consider are its physical and chemical properties. From the last lab, we determined that a physical property was something that you could observe without a chemical reaction occurring. A chemical property is a property that can only be observed when a chemical change occurs. A chemical property indicates how likely that the material will be involved in a chemical reaction.
Prelab
1.) Why is copper no longer used in pennies?
2.) What materials did the U.S use to make pennies during World War II?
3.) Why did the U.S. go back to using copper after 1943?
4.) Ultimately what are our pennies made from today?
5.) Predict: What is a chemical property of zinc.
Procedure
How might you test the chemical properties of zinc? What materials might you need?
Data
1.) Identify the physical properties of a penny before made before 1982?
2.) Identify the physical properties of a penny made after 1982?
3.) Identify one chemical property of a penny made after 1982?
Analysis
1.) Why do we have copper on the outside of our pennies?
2.) If you were given the job to design a new penny, what physical properties would you look for when choosing a material?
3.) If you were given the job to design a new penny, what chemical properties would you look for when choosing a material?
4.) If you were given the job to design a new penny, what other characteristics would you look for when choosing a material?
Conclusion
Was your hypothesis correct?
Suggest a research question that you might like to investigate further.
Designing the Penny
During World War II, copper metal was in short supply. In order to conserve the reserves of copper, the United States Government began to create pennies out of other materials. At first, they created pennies that were made of zinc plated steel. Due to the high reactivity of zinc, the pennies quickly corroded. These pennies were referred to as "white cents" or "steel cents". They were only produced for one year and copper was again used. As time went by, copper became too expensive to use and in the early 1980s, a new penny was developed. This penny used copper, but only on the outside. The more affordable metal zinc was used on the inside of the penny.
Often times the cost of a material greatly impacts it's use. Other things to consider are its physical and chemical properties. From the last lab, we determined that a physical property was something that you could observe without a chemical reaction occurring. A chemical property is a property that can only be observed when a chemical change occurs. A chemical property indicates how likely that the material will be involved in a chemical reaction.
Prelab
1.) Why is copper no longer used in pennies?
2.) What materials did the U.S use to make pennies during World War II?
3.) Why did the U.S. go back to using copper after 1943?
4.) Ultimately what are our pennies made from today?
5.) Predict: What is a chemical property of zinc.
Procedure
How might you test the chemical properties of zinc? What materials might you need?
Data
1.) Identify the physical properties of a penny before made before 1982?
2.) Identify the physical properties of a penny made after 1982?
3.) Identify one chemical property of a penny made after 1982?
Analysis
1.) Why do we have copper on the outside of our pennies?
2.) If you were given the job to design a new penny, what physical properties would you look for when choosing a material?
3.) If you were given the job to design a new penny, what chemical properties would you look for when choosing a material?
4.) If you were given the job to design a new penny, what other characteristics would you look for when choosing a material?
Conclusion
Was your hypothesis correct?
Suggest a research question that you might like to investigate further.